Synthesis, Crystal Structures, and Properties of Copper(II), Zinc(II), and Cadmium(II) Coordination Polymers Based on 5‐Nitro‐isophthalate and 1,2‐(2‐Pyridyl)‐1,2,4‐triazole

Three coordination polymers, namely {[Cu(5‐nipa)(L 22 )](H 2 O) 2 } n ( 1 ), [Zn(5‐nipa)(L 22 )(H 2 O)] n ( 2 ), and {[Cd 2 (5‐nipa) 2 (L 22 )(H 2 O) 3 ](H 2 O) 3.6 } n ( 3 ), were prepared under similar synthetic method based on 1,2‐(2‐pyridyl)‐1,2,4‐triazole (L 22 ) and ancillary ligand 5‐nitro‐isophthalic acid (5‐H 2 nipa) with Cu II , Zn II , and Cd II perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X‐ray diffraction (PXRD) patterns. Single‐crystal X‐ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square‐pyramid for Cu II in 1 , octahedron for Zn II in 2 , to pentagonal‐bipyramid for Cd II in 3 . The L 22 ligand adopts the same (η 3 ,μ 2 ) coordination fashion in complexes 1 – 3 , while the carboxyl groups of co‐ligand 5‐nipa 2– adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3 . These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1 – 3 and photoluminescent properties of 2 and 3 were also studied in the solid state.